The invention relates to a television camera comprising a pickup lens and an elongate pickup unit which is aligned with respect to the lens. The pickup unit includes a pickup tube which is arranged in a holder having a longitudinal axis. The holder also has a slide on which the pickup unit can be displaced along the longitudinal axis in the direction of the pickup lens. An adjusting lever, which is coupled to the pickup unit by way of a part which is situated between the ends of the lever, is provided for displacing the pickup tube along the slide. One end of the lever is directly coupled to the holder at a wall of the holder which extends transversely to the slide. The other end of the lever is coupled to the wall by an adjusting member.
A television camera of the kind described above is disclosed in German Patent No. 19.17.673. The pickup unit in this Patent is arranged in a holder with a slide. The slide radially supports the pickup unit, near the front and rear of the pickup unit, by way of two rigid members and two resilient members. The holder also has a transverse wall through which the front of the pickup unit projects and to which the adjusting lever is coupled. The adjusting lever has a hole midway between its ends. A shaft is journalled in this hole. The shaft is connected to a pin which in turn is coupled to a fork. The fork is mounted on the pickup unit and projects in the lateral direction. Furthermore, one end of the adjusting lever has a fork which engages a shaft connected to the transverse wall. The other end of the adjusting lever has a hole in which there is arranged a shaft. The shaft has a threaded hole directed transverse therethrough.
An adjusting bolt, which is connected to the transverse wall of the holder, is fixed axially and serves as an adjusting member by screwing it into the threaded hole in the shaft. When this bolt is turned, the adjusting lever pivots around the shaft connected to the transverse wall. Because the adjusting lever is coupled to the pickup unit in the described manner, the pickup unit is displaced in the axial direction in the holder. The pickup lens and the pickup unit can thus be adjusted with respect to each other so that a sharp television picture is obtained.
A rather large number of parts are required for adjusting the pick-up unit with respect to the pickup lens in the described television camera. For accurate adjustment; these parts must all be accurately manufactured and accurately mounted in the camera. Therefore, the described television camera is not very well suited for manufacture in large quantities.
It is an other disadvantage of the known camera that the adjusting lever, which can be moved by the adjusting bolt, is coupled to a laterally projecting fork arranged on the pickup unit. Consequently, the adjusting lever not only exerts an axial force on the pickup unit, but also exerts a torque which tends to twist the pickup unit in the holder. If, moreover, the parts are not very accurately manufactured so that they do not fit without play, the movement of the pickup unit in the holder during adjustment may be irregular. In this case, each movement begins with a lurch, making it difficult to properly adjust the pickup unit.